SANDWICH — The family trees of more than a dozen Cape Cod pets will have no more branches after a visit Tuesday to the Spay Waggin.'

The Animal Rescue League of Boston's mobile truck provides low-cost spaying and neutering surgeries around the Cape and South Shore for dog and cat owners who can't afford the procedures at local veterinary clinics.

A visit to the Spay Waggin,' which Tuesday was parked in the Sullivan Tire store lot, means no more unplanned litters, which can be a costly burden to owners and animal shelters, league officials say.

What's inside?

A veterinarian, two veterinary technicians, a preparation area, surgical suite, recovery ward, space to accommodate up to 40 animals and lots of animal-specific medical equipment.

What does the vet say about spaying/neutering?

"We just think it's really important for the individual animal because it prevents diseases and behavior problems that people don't like to have in their home," said Kate Gollon, a rescue league shelter and community veterinarian. "It's also great from a population health standpoint; we're reducing the number of animals that enter shelters."

What does a pet owner say?

Karen Wallace, of Harwich, dropped off her 6-month-old female terrier mix named Shelby. "They just make it so easy for people, so there's really no excuse not to spay or neuter your pet. It's so convenient and affordable and helps people do the right thing."

Spay Waggin' stats:

In 2013, the Spay Waggin' treated more than 4,000 cats and dogs at its monthly stops at locations throughout Barnstable, Bristol, and Plymouth counties. That was 1,000 more than in 2012.

The Spay Waggin,' which is by appointment only, makes periodic trips to the South Shore and Cape Cod. For complete information call 877-590-7729, email spaywaggin@arlboston.org or visit arlboston.org/spay-waggin.